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Viewing 1 to 30 of 10498
2016-04-15
Journal Article
2015-01-9020
Emre Sert, Pinar Boyraz
Abstract Studies have shown that the number of road accidents caused by rollover both in Europe and in Turkey is increasing [1]. Therefore, rollover related accidents became the new target of the studies in the field of vehicle dynamics research aiming for both active and passive safety systems. This paper presents a method for optimizing the rear suspension geometry using design of experiment and multibody simulation in order to reduce the risk of rollover. One of the major differences of this study from previous work is that it includes statistical Taguchi method in order to increase the safety margin. Other difference of this study from literature is that it includes all design tools such as model validation, optimization and full vehicle handling and ride comfort tests. Rollover angle of the vehicle was selected as the cost function in the optimization algorithm that also contains roll stiffness and height of the roll center.
2016-04-05
Journal Article
2015-01-9152
André Lundkvist, Arne Nykänen, Roger Johnsson
Abstract Many of the information systems in cars require visual attention, and a way to reduce both visual and cognitive workload could be to use sound. An experiment was designed in order to determine how driving and secondary task performance is affected by the use of information sound signals and their spatial positions. The experiment was performed in a driving simulator utilizing Lane Change Task as a driving scenario in combination with the Surrogate Reference Task as a secondary task. Two different signal sounds with different spatial positions informed the driver when a lane change should be made and when a new secondary task was presented. Driving performance was significantly improved when both signal sounds were presented in front of the driver. No significant effects on secondary task performance were found. It is recommended that signal sounds are placed in front of the driver, when possible, if the goal is to draw attention forward.
2016-04-05
Technical Paper
2016-01-0148
Diljith Kunnamcherry Muthuvana
The main purpose of the V2X system is to enhance the safety and efficiency of the driver. Since the Automotive diaspora is now moving for a safe, connected and intelligent mobility. The V2X system allows communication over the air with other V2X traffic participants, the participants include the target vehicles or roadside units equipped with a V2X system and uses this information exchange to warn the driver about potential road hazards, thereby extending a vehicle’s field of vision. This will in turn enhance the safety and efficiency of the driver. One possible scenario could be that the V2X system receives information from a vehicle involved in an accident and then warns about this accident ahead via the HMI display. The V2X system also collects vehicle data and prepares it to generate messages send out to other V2X participants over the air.
2016-04-05
Technical Paper
2016-01-0397
Wenxin Qin, Sandip Datta, Weidong Zhang
In automotive chassis, body and powertrain finite element numerical analysis, more and more analysts and engineers like to adopt 3D complex FEA models along with improved computer hardware and software. The advantages of 3D FEA model are (1) looked like real model in vision; (2) simulation response is more vivid; (3) easily to discover the mistakes by watching simulation response. The drawbacks of 3D FEA model are (1) more pre/post process works and computation time; (2) numerical divergence is a challenging issue in nonlinear and contact situations and debug becomes difficulty; (3) sometimes accumulated numerical errors will cover the actual response. Therefore, it is necessary to explore what kinds of 3D FEA situations can be successfully converted by the simple 2D plan FEA models.
2016-04-05
Technical Paper
2016-01-0395
Anindya Deb, Clifford C. Chou, Gunti R. Srinivas, Sanketh Gowda, Goutham kurnool
An attractive strategy for joining non-ferrous or non-metallic substrates is through adhesive bonding. This technique of joining also offers the functionality for joining dissimilar materials. However, doubts are often expressed on the ability of such joints to perform on par with other mechanical fastening methodologies such as welding, riveting, etc. In the current study, adhesively-bonded single lap shear (SLS) and double lap shear (DLS) joints are studied initially under quasi-static (at a cross-head speed of 1 mm/min) tensile and flexural loading using steel and aluminum substrates, and an epoxy-based adhesive of a renowned make. The study includes usage of similar substrates made of only steel or aluminum, or a combination of steel and aluminum substrates. Load-displacements curves for bonded joints are presented for varying overlap lengths.
2016-04-05
Technical Paper
2016-01-1403
Jeff D. Colwell, Christopher D. Henry
Data from a full-scale vehicle burn test involving a cargo van illustrated that the fire progressed in distinct stages. After the fire was initiated on the driver’s side of the engine compartment, it slowly grew over a relatively long time period to involve nearby locations. Once the peak temperature reached about 540°C, the rate of flame spread increased such that over the next 4 minutes the fire spread across the entire engine compartment. In the next stage of the fire, which occurred shortly after full involvement of the engine compartment, the fire spread into the passenger compartment. A strong vertical temperature gradient developed from the ceiling to the floor and as the passenger compartment became fully involved, the passenger compartment temperatures both increased and became more uniform. Although oxidation and melted aluminum patterns were created during the burn test, neither correlated well with the origin of the fire.
2016-04-05
Technical Paper
2016-01-1499
Willy Klier, Thomas Lich, Gian Antonio D’Addetta, Heiko Freienstein, Armin Koehler, Bastian Reckziegel, Zerong Yu
On the way to automated driving, the market penetration of surround sensing systems will rapidly increase in the upcoming years. The respective technical progress in the areas of driver assistance and active safety leads to a numerous and valuable information and signals to be used prior, during and even after an accident. Car makers and suppliers can make use of this new situation and develop new integrated safety functions to further reduce the number of injured and even deaths in car accidents. Nevertheless, the base occupant safety remains the core of this integrated safety system in order to ensure at least a state-of-the-art protection even in vehicles including partial, high or full automation. Current networked safety systems comprehend a point-to-point connection between single components of active and safety systems. The optimal integration requires a much deeper and holistic approach.
2016-04-05
Technical Paper
2016-01-0436
Bolin Zhao, Chen Lv, Junzhi Zhang, Theo Hofman, Maarten Steinbuch
Distinguished from the conventional internal combustion engine vehicles, most of the pure electric vehicles are equipped with only a fixed-ratio reduction gear, because of the wide speed range of the electric motor. For most of the vehicle’s speed and acceleration requirements, they can be satisfied through application of only a fixed-ratio reduction gear. However, within some speed range, the operation efficiency of the electric motor is relatively low, which affects the overall energy efficiency of the electric vehicle. Thus, application of a two-speed gearbox is able to remain the electric motor working within high-efficiency range during the whole operation conditions, which has a good potential to further improve the electric vehicle’s energy economy. Based on the above analysis, in this paper, gear ratios of a two-speed transmission system are optimized for an electric passenger car.
2016-04-05
Technical Paper
2016-01-1531
Dale E. Halloway
Occupant Kinematics in Distinct Types of Far-side Impacts Objective: Occupant contacts not on a trajectory not in line with a response to the resultant impact vector are seen as the consequence of post-impact vehicle rotation. This analysis evaluates field data for indications the trajectory occupant contacts indicate in far-side impacts is affected by the acceleration of the vehicle. Methods: Using the WinSMASH calculated moment arm a classification scheme was devised. WinSMASH calculates and reports moment arm length and sign. Moment arm length was used to classify impacts as ‘centric’ or ‘eccentric’ relative to the vehicle center of gravity. A query was made for far-side impacts in CIREN. 111 cases were reviewed and WinSMASH re-run. The results were used to classify impacts by the crush profile center-of-damage and principal direction of force. All AIS 2+ injuries were located on whole body and specific anatomic region mannequins.
2016-04-05
Technical Paper
2016-01-1505
William W. Van Arsdell, Paul Weber, Charles Stankewich, Brian Larson, Ryan Hoover, Richard Watson
This paper investigates the role that load limiters play with respect to the performance of occupant protection systems. Modern occupant protection systems consist of not just the seat belt, but also airbags, interior vehicle surfaces and vehicle structure. Modern seat belts very often incorporate load limiters as well as pretensioners. Published research has established that load limiters and pretensioners increase the effectiveness of occupant protection systems. Some individuals have argued that load limiters with higher deployment thresholds are always better than load limiters with lower deployment thresholds. Similarly, they have argued that load limiters should always include stops that limit the amount of webbing deployed due to load limiter actuation. Through testing and analysis, we have investigated this hypothesis and in this paper we present test data as well as a discussion to this data and engineering mechanics to explain why this hypothesis is incorrect.
2016-04-05
Technical Paper
2016-01-0427
Chang Qi, XiaoLong Feng, Yu du, Shu Yang, Da-Zhi wang
Large rear-dump mining trucks often suffer from rock impacts which cause adverse vibration during loading operation, resulting in structural damage and deteriorated fatigue life of the body. To decrease the body vibration under heavy rocks’ impact loading, an innovative active suspension system concept was put forward for the rear-dump mining trucks in this work. The new system was developed using simulation methods in three steps. Firstly, a simplified multi-body system dynamic model of a 360t load capacity rear-dump mining truck under rock impact was built in ADAMS as a base model. Secondly, by using the joint simulation method, the base model was translated into a system function module in MATLAB, and an active PID control system to adjust the suspension force was designed base on the modules in SIMULINK. Finally, parameter optimization was conducted to guarantee the proposed control system a better damping performance during the loading process.
2016-04-05
Technical Paper
2016-01-1658
Jie Huang, Lu Xiong, Songyun Xu, Zhuoping Yu
With the development of the electrification of the automobile, electronic hydraulic brake system is gradually applied. Many companies have introduced products related to integrated electronic hydraulic brake system(I-EHB)- a kind of the electronic hydraulic brake system. In this paper, an integrated electronic hydraulic brake system is introduced, which uses the motor to drive the reduction mechanism as a power source for braking. The reduction mechanism is composed of a turbine, a worm, a gear and a rack. A control method based on command feed-forward is proposed to improve the hydraulic pressure control of integrated electronic hydraulic brake system(I-EHB). Based on previous research, we simplify the system to first order system, and the theoretical design of the command feed-forward compensator is carried out.
2016-04-05
Technical Paper
2016-01-0435
Lirong Wang
Speed bumps are a common traffic calming device that uses vertical deflection to slow motor-vehicle traffic in order to improve traffic safety conditions. Such vertical raising of road pavement had been studied and commonly used as a passive method to reduce the speed of vehicle. Speed bumps generally slow vehicle speed to 5–10 mph (8.0–16.1 km/h), and some to 10–20 mph (16–32 km/h). On one side, speed bumps/humps effectively calm traffic speed to protect pedestrians. On the other side, it may cause vehicle damage and passenger discomfort. In Sweden, an evaluation of spinal stress in bus drivers against ISO 2631-5 required that a driver shall encounter less than 150 bumps in a day at the maximum acceptable speed 10 km/h. When a vehicle touches a speed bump, the speed bump receives the energy transferred by the weight and velocity of the vehicle. Harvesting the vibration energy from speed bump becomes a valid solution in areas where grid electricity is economically available.
2016-04-05
Technical Paper
2016-01-1470
Nathan A. Rose, Neal Carter, Gray Beauchamp
Calculating the speed of a yawing and braked vehicle often requires an estimate of the rate at which the vehicle decelerated over the course of its trajectory. During a steering induced yaw, the rotational velocity of the vehicle will typically be small enough that it will not make up a significant portion of the vehicle energy. However, when a yaw is impact induced and the resulting yaw velocity is high, the rotational component of the vehicle’s kinetic energy can be significant relative to the translational component. In such cases, the rotational velocity can have a meaningful effect on the rate at which the vehicle decelerates. In addition to the effects of rotational energy on the deceleration rate, high yaw velocities can also cause steering angles to develop at the front tires because the frictional forces between the tires and ground cause the yaw rotation of the tires to lag behind the yaw rotation of the vehicle.
2016-04-05
Technical Paper
2016-01-1462
Louis R. Peck, Mu-Hua Cheng
Three targeted vehicles of varying size were measured using an optimized, practical photogrammetry technique and the results were compared to measurements acquired via total station. The photogrammetry method included the use of a field-calibrated DSLR camera equipped with a fixed 20mm lens, retro-reflective targets sized for vehicular modeling, and a CNC-machined scale bar. Eight photographs were taken from proper angles and processed using a commercially available photogrammetry package, and that data was merged with the total station data using a cloud-to-cloud registration process for point-to-point comparison of positional data. The average residual between corresponding photogrammetry and total station points was 1.7 mm (N 258, SD = 0.8 mm) with a 95% confidence level of 3.3 mm. Considering this low residual, one of the sample vehicles was re-measured using a high accuracy FARO Arm for comparison to the photogrammetry technique.
2016-04-05
Technical Paper
2016-01-0403
Devendra M. Oza, Abhijit Londhe
Stiffness evaluation for the components made from natural rubber have been attempted here using Finite Element simulation technique. Conventional method for extraction of the stiffness with metallic parts like steel using linear approach is no more valid in rubber (elastomers). Unique properties of elastomers like sustaining strains up to 500% due to large deformation under loading (displacement unveils non-linear behavior with applied load), exhibiting significant damping property because of viscoelasticity and nearly incompressible in nature (no change in volume appreciably with stress) creates a need to seek for special material model and capture non-linear behavior. Stress vs strain behavior of elastomers under all possible loading conditions calls for physical sample test in uni-axial tension, uni-axial compression, bi-axial tension, planar shear and volumetric test. Two suspension rubber mounts and one engine mount have been analyzed with the current simulation technique.
2016-04-05
Technical Paper
2016-01-1480
Jakub Zebala, Wojciech Wach, Piotr Ciępka, Robert Janczur
This article presents the results of an analysis of the yaw marks left by a car with nominal pressure in all tires and with zero pressure in one rear tire. The analysis is a continuation of research on influence of reduced tire pressure on car lateral dynamics in a passing maneuver, discussed at the SAE Congress in 2014. Preliminary analysis of yaw marks has shown, that a wheel with zero pressure deposits a yaw mark whose geometry differs from the yaw mark made by a wheel with nominal pressure based on which we could calculate: critical speed, slip angle and longitudinal wheel slip. The aim of the presented research was to analyze the yaw marks left by car with zero pressure in one rear wheel in order to check the possibility of determining the vehicle critical speed, slip angle and longitudinal wheel. It was reached by performing bench and road tests during which the vehicle motion parameters were recorded using GPS Data Logging System.
2016-04-05
Technical Paper
2016-01-0405
Fupin Wei, Li Xu, Chen Cao, Youmei Zhao
Crash Test Dummies are very important tools to evaluatethe vehicle safety performance. In order to ensure dummy performance during the crash tests, the dummy components need to be calibrated. In the neck calibration procedure, the flexion angle is the most important parameter, which is the head rotation respect to the neckbase. To get the flexion angle, couples of rotary potentiometers should be mounted either on the calibration fixture or on the dummies. The flexion angle is then calculated from those angles. There are two potentiometers in the Hybrid III family dummies, three potentiometers in ES2, ES2-RE, SID-IIs, BioRid, and WorldSid dummies. In the calibration certification,maximum flexion angle and time occurred should be within certain range in the Hybrid III family dummies while for the ES2, SID-IIs, BioRid, and WorldSid dummies, not only the flexion angle, but also the otherangles should meet the maximum angle and timeoccurred corridors.
2016-04-05
Technical Paper
2016-01-1478
William T. Neale, David Hessel, Daniel Koch
This paper presents a methodology for tracking the motion of objects, such as vehicles, pedestrians, or cyclists that are visible in video footage captured with only one camera. Objects are tracked in the video footage based on their pixel properties. This tracking process results in two dimensional coordinate data based on the video footage resolution. This data can then be transformed to three dimensional data where the geometry of the scene that is visible in the video footage is known. This paper explains the automated process of first tracking pixels in the video footage, and then remapping the 2D coordinates onto three dimensional geometry using previously published projection mapping techniques. What is unique in this process, that is not unavailable in other photogrammetry tracking process is the time reduced in tracking the object, since it is automated, and that the shape and size of the object being tracked does not need to be known.
2016-04-05
Technical Paper
2016-01-1461
William T. Neale, David Danaher, Sean McDonough, Tomas owens
Many of the smart phone devices widely available on the market today have built in functionality and equipment that may prove useful in certain procedures of accident reconstruction testing and analysis. Two technologies found on many of the devices include accelerometers and GPS tracking. Being capable of tracking the position, speed and acceleration of a vehicle being tested is obviously useful, but can a smart phone, enabled with this technology, provide veritable data for use in accident reconstruction? And what factors would affect the accuracy? This paper presents on this topic in three segments. First, the paper provides an overview of the accelerometer and GPS technology that is built in to smart phone devices. Second, this paper evaluates several versions of smart phones and related software that allows a user to track speed, position, acceleration, temperature, and elevation. The smart phones are tested in scenarios simulating walking, running, biking, and driving.
2016-04-05
Technical Paper
2016-01-0401
Yucheng Liu
A new beam element is developed, which is capable of capturing thin-walled beam’s collapse mechanisms under dynamic load such as impact load. Such beam element can be used to create simplified finite element models for crashworthiness analysis and simulation and, therefore, will significantly reduce the modeling effort and computing time. The formulation of the developed beam element has been implemented into the User Defined Element Interface of LS-DYNA and used for creating a simplified thin-walled beam model. In the future, the new beam element will be used for crashworthiness analysis for further validation.
2016-04-05
Technical Paper
2016-01-0161
Valentin Soloiu, Imani Augusma, Deon Lucien, Mary Thomas, Roccio Alba-Flores
This study presents the design and development of a vehicle platform with intelligent sensors that has the capabilities to drive independently and cooperatively on roads. An integrated active safety system has been designed to optimize the human senses using ultrasonic infrared sensors and transmitter/receiver modules, to increase the human vision, feel and communication for increased road safety, lower congestion rates, and decrease CO2 emissions. Ultrasonic sensors mounted on the platform, emitted longitudinal 40 kHz waves and received echoes of these sound waves when an object was within its direction. The duration was converted to a distance measurement to detect obstacles as well as using distance measurement threshold values to implement adaptive cruise control. Infrared sensors equipped with an IR LED and a bipolar transistor detected a change in light intensity to identify road lanes.
2016-04-05
Technical Paper
2016-01-1483
The objective of this study is to assess the accuracy of using high impact speed frontal barrier crash tests to predict the deformation energy for a lower impact speed frontal barrier crash. To make this prediction, two key assumptions were made: the frontal barrier crash tests are repeatable for the same model vehicle, and the rebound phase in the force vs deflection curve is similar for the same vehicle model regardless of impact speed. For each vehicle to barrier test, the vehicle’s force vs. deflection curve will be created by synchronizing the barrier’s load cell data with a double integration of the vehicle’s accelerometer data. The deformation energy dissipated during each barrier impact will be calculated by integrating the corresponding force vs. deflection curve. To verify that all deformation energy was accounted for in the test data, the deformation energy will be used to calculate the test EBS.
2016-04-05
Technical Paper
2016-01-1503
Typical seatbelts have a locking mechanism referred to as an emergency locking retractor. This locking mechanism operates in response to an acceleration or deceleration input or to the sudden extension of the seatbelt. However, because the clothing of vehicle occupants can produce slack in the seatbelt, it is possible that a vehicle occupant may move forward before being restrained by the seatbelt. In these types of situations, if the vehicle occupants do not maintain their posture through their own strength muscles, by inertia of the vehicle, the posture of the vehicle occupants may change due to the slack caused by the way in which the seatbelts are used. To suppress the forward movement of the occupant, the motorized seat belt had been developed. Motorized seatbelt systems that retract seatbelts using motors are being mass-produced by many manufacturers.
2016-04-05
Technical Paper
2016-01-1111
Ankur Sharma, Harish Kumar Gangwar, dipak dabhole, S.B. Pathak, VIvek Dwivedi, Amit Nigam
Abstract Hill start assistance developed for buses equipped with AMT The AMT (Automatic Mechanical Transmission) has attracted increasing interest of automotive researches, because it has some advantages of MT (Manual Transmission) and of AT(Automatic Transmission), such as low cost, high efficiency, easy to use and good comfort. The hill-start assistance is an important feature of AMT. The vehicle will move backward, start with jerk, or cause engine stalling if failed on the slope road. For manual transmission, hill-start depends on the driver's skills to coordinate with the brake, clutch and throttle pedal to achieve a smooth start. However, the AMT removes the clutch pedal, thus the driver can’t perceived the clutch position. So it is difficult to hill-start for the driver with AMT without hill-start control strategy. This paper discussed about the hill start control strategy and its functioning.
2016-04-05
Technical Paper
2016-01-1640
An integrated-electro-hydraulic brake system(I-EHB) for automotive is presented to fulfill the requirements of active safety. Based on the analysis of current electro-hydraulic brake systems, regulation requirements and the requirements for automotive brake system, the operating mode requirements of I-EHB are formed. Furthermore, system topological structure and a conceptual design are proposed. After the selection of key components, the parameter design is accomplished by modeling the system. According to the above-mentioned design method, an I-EHB prototype and test rig is made. Through the test rig, characteristics of the system are tested. Results show that this I-EHB system responded rapidly. Upon the experimental results, increasing pressure response time of I-EHB is 53% shorter than that of conventional brake system and reducing pressure response time of I-EHB is 70% shorter than that of conventional brake system. The tracking performance of I-EHB is good.
2016-04-05
Technical Paper
2016-01-0110
Mohammad Huq, Douglas McConnell
Adaptive Cruise Control (ACC) runs with a set of parameters that determine how the ACC performs. Some of these parameters are tunable to some degree through HMI and the rests are pre-determined. The proposed Behavior Trainable ACC (BTACC) is able to learn all or some of these parameters from driving behavior of the driver. To develop BTACC adapted to the driver’s driving behavior, the ACC keeps collecting driving data such as set speed, acceleration, deceleration, head way settings, etc., of the vehicle over time and keeps updating the related parameters. After training is over, the driver is able to drive the vehicle in BTACC mode, when the vehicle would drive itself according to driving behavior of the driver, young or elderly, and thus, provide the drivers with a higher level of safety and comfort. BTACC can be embedded with an existing ACC module so that the drivers may choose either ACC or BTACC.
2016-04-05
Technical Paper
2016-01-1351
Simhachalam Bade
Aluminum alloys are widely used in the transportation because of their high strength-to-weight ratio and outstanding capability in absorbing energy. In this paper, performance of bumper with crash tubes using aluminum alloy AA6061 and AA7003 materials is compared using numerical methods. Quasi-static test is simulated using the LS-DYNA implicit finite element program. Bumper and crash tubes are included in the finite element model. Symmetric Holes are provided in the crash tubes to initiate crushing. True stress-plastic strain curves from the tensile test are used in the static simulation. Displacement is applied to the bumper using Rigdwall geometric wall motion. The energy absorbed by bumper and crash tubes are compared. Dynamic simulation is done using LS-Dyna explicit program. True stress-true plastic strain curves at different strain rates from the literature is used in the dynamic simulation of AA7003 material to study the strain rate effects on impact behavior of tubes.
2016-04-05
Technical Paper
2016-01-0046
Markus Ernst, Mario Hirz, Jurgen Fabian
A steady increasing share and complexity of automotive software is a huge challenge for quality management during software development and in-use phases. In cases of faults occurring in customer’s use, warranty leads to product recalls which are typically associated with high costs. To avoid software faults efficiently, quality management and enhanced development processes have to be realised by the introduction of specific analysis methods and Key Process/Performance Indicators (KPIs) to enable objective quality evaluations as soon as possible during product development process. The paper introduces the application of specific analysis methods by using KPIs and discusses their potential for automotive software quality improvement. The aim is to support quality evaluation and risk-analysis for the release process of automotive software.
2016-04-05
Technical Paper
2016-01-1530
Yury Chudnovsky, Justin Stocks-Smith, Jeya Padmanaban, Joe Marsh
A comprehensive review of technical literature addressing injury risk in near- and far-side impacts was performed, and NASS/CDS data (1998-2013) was examined to address serious injury rates, sources, and nature for belted drivers in side impacts. Frequency and severity of near- and far-side impacts by crash severity (delta-V) were compared for older (1994 – 2007 MY) and newer vehicles (2008+ MY). For 2008 MY, individual cases were examined for serious injury factors in far-side impacts. Near- and far-side impacts were identified using principal direction of force and general area of damage. Results show that about 90% of NASS/CDS side impacts have a delta-V under 15 mph for both older and newer cars. The serious injury rate for belted drivers in older cars is 5.5% for near-side crashes and 1.2% for far-side crashes. For newer models, the serious injury rate for belted drivers is 2.5% near-side and 0.5% far-side.
Viewing 1 to 30 of 10498